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331.
基于网络环境的服务发展与创新已成为经济发展的新引擎。本文在分析网络环境下服务特征基础上,探讨了其对服务科学与创新管理研究的影响。结合我国社会经济发展对现代服务快速增长的需求,本文提炼了服务科学研究的三类基本科学问题,包括服务价值的内涵与度量,服务资源的要素及其价值生成,和服务关系的界定与形成问题;提出了服务与创新管理的四个重要研究领域,即:服务生态系统的形成与演化,服务资源要素的组织与协调,服务的关联与融合和社会服务运作管理问题。在四个重要研究领域的进一步分析中,论文以一个异质数据服务资源的组织与融合为例,描述了服务资源组织与协调的一个具体问题,说明了已有研究方法解决该问题的困难,和未来该问题研究需要关注的重点;另以平台服务中基于价值和关系的服务定价问题为例,说明服务关联与融合研究的挑战及其未来研究的努力方向。 相似文献
332.
Discrete‐choice models are widely used to model consumer purchase behavior in assortment optimization and revenue management. In many applications, each customer segment is associated with a consideration set that represents the set of products that customers in this segment consider for purchase. The firm has to make a decision on what assortment to offer at each point in time without the ability to identify the customer's segment. A linear program called the Choice‐based Deterministic Linear Program (CDLP) has been proposed to determine these offer sets. Unfortunately, its size grows exponentially in the number of products and it is NP‐hard to solve when the consideration sets of the segments overlap. The Segment‐based Deterministic Concave Program with some additional consistency equalities (SDCP+) is an approximation of CDLP that provides an upper bound on CDLP's optimal objective value. SDCP+ can be solved in a fraction of the time required to solve CDLP and often achieves the same optimal objective value. This raises the question under what conditions can one guarantee equivalence of CDLP and SDCP+. In this study, we obtain a structural result to this end, namely that if the segment consideration sets overlap with a certain tree structure or if they are fully nested, CDLP can be equivalently replaced with SDCP+. We give a number of examples from the literature where this tree structure arises naturally in modeling customer behavior. 相似文献
333.
When network effects are important and technology is rapidly improved, this study explores the relative optimality of five product introduction strategies of a durable goods manufacturer: (1) replacement, (2) skipping, (3) a delayed line, (4) shelving, and (5) line‐extension. Using a two‐period analytical model, we show how the type of compatibility—either full or backward compatibility—and the magnitude of the network effect influence the manufacturer's preference for the above strategies. Our analysis reveals that only the strategies (1)–(3) above can be optimal; and the optimal strategy varies with network strength. Further, the type of compatibility can dramatically change the profitability under each optimal strategy; for instance, while backward compatibility can increase the profitability of replacement under certain conditions, it always reduces the profitability of a delayed line. We also illustrate that if compatibility were a choice, although backward compatibility may be observed widely in practice, the parametric region for its optimality is relatively more restricted than that of full compatibility. 相似文献
334.
335.
中、韩建交以来,韩国在对华投资额、投资地区以及投资领域等方面都有较大的突破。但是,韩国对华投资中存在一些问题,如投资规模较小、投资领域较窄、本土化战略不足等。这就需要中、韩两国政府积极采取相应措施,加大吸引韩商投资的力度,优化韩商投资的地区布局和产业结构,打造引资平台和改善投资环境,从而推动中、韩两国企业合作步入一个新的发展阶段。 相似文献
336.
吸毒人群社会支持网研究对重庆市南岸区戒毒所的调查 总被引:7,自引:0,他引:7
本文通过对重庆市南岸区戒毒所的调查,采用社会支持网分析方法,发现吸毒人员的社会支持网规模很小,吸毒网络具有秘密性和牢固性。其相识关系提供毒品支持,朋友关系和亲戚关系提供情感和经济支持。吸毒人员的吸毒年限、有抢劫和偷盗行为对注射吸毒行为和共用针头注射吸毒行为有明显的影响等一系列特征。 相似文献
337.
Kimberley Kolb Ayre Colleen A. Caldwell Jonah Stinson Wayne G. Landis 《Risk analysis》2014,34(9):1589-1605
Introduction and spread of the parasite Myxobolus cerebralis, the causative agent of whirling disease, has contributed to the collapse of wild trout populations throughout the intermountain west. Of concern is the risk the disease may have on conservation and recovery of native cutthroat trout. We employed a Bayesian belief network to assess probability of whirling disease in Colorado River and Rio Grande cutthroat trout (Oncorhynchus clarkii pleuriticus and Oncorhynchus clarkii virginalis, respectively) within their current ranges in the southwest United States. Available habitat (as defined by gradient and elevation) for intermediate oligochaete worm host, Tubifex tubifex, exerted the greatest influence on the likelihood of infection, yet prevalence of stream barriers also affected the risk outcome. Management areas that had the highest likelihood of infected Colorado River cutthroat trout were in the eastern portion of their range, although the probability of infection was highest for populations in the southern, San Juan subbasin. Rio Grande cutthroat trout had a relatively low likelihood of infection, with populations in the southernmost Pecos management area predicted to be at greatest risk. The Bayesian risk assessment model predicted the likelihood of whirling disease infection from its principal transmission vector, fish movement, and suggested that barriers may be effective in reducing risk of exposure to native trout populations. Data gaps, especially with regard to location of spawning, highlighted the importance in developing monitoring plans that support future risk assessments and adaptive management for subspecies of cutthroat trout. 相似文献
338.
《Omega》2014
In this paper, we present an access network design problem with end-to-end quality of service (QoS) requirement. The problem can be conceptualized as a two-level hierarchical location-allocation problem on the tree topology with nonlinear side constraints. The objective function of the nonlinear mixed integer programming model minimizes the total cost of switch and fiber cable, while satisfying demand within the prescribed level of QoS. By exploiting the inherent structure of the nonlinear QoS constraints, we develop linearization techniques for finding an optimal solution. Also, we devise an effective exact optimal algorithm within the context of disjunctive constraint generation. We present promising computational results that demonstrate the effectiveness of the proposed solution procedure. 相似文献
339.
高慧 《长春工程学院学报(社会科学版)》2017,18(1)
2014年7月1日,新修订的企业会计准则率先在所有执行企业会计准则的企业范围内施行,这意味着企业的财务核算、财务报表等面临新的问题和挑战.长期股权投资是企业会计核算中的重点和难点,其会计核算方法比较复杂,不同的会计核算会对企业的财务产生不同的影响.本次长期股权投资的修订,规范了长期股权投资的会计核算方法,使其持续趋同于国际会计准则,有利于我国对外经济合作,有利于适应社会经济的发展.本文主要剖析了长期股权投资准则修订前后的变化,对其主要会计核算进行举例分析,并分析其对企业财务的影响. 相似文献
340.
柏培文 《厦门大学学报(哲学社会科学版)》2012,(4):82-89
估算全国和省际人力资本水平是经济增长研究所不能回避的问题。当前的研究主要采用教育年限法、物质投入法、生产函数法、人力资本回报法、人力资本特征与收入法和J-F终生收入法等六种方法。多角度比较和判别,可以验证生产函数法测算的各年相对人力资本水平较为可靠。使用生产函数法估算全国和各省的1952-2008年的人力资本存量,可刻画统一单位衡量的全国和各省人力资本水平。总体来说,全国和各省人力资本水平呈增长状态,各省人力资本存量以及增长速度存在明显差异。 相似文献